The invention is in the field of medical devices. More specifically, the invention relates to devices for the treatment of urinary incontinence.
Several disorders of the urinary tract are known. Among these are urinary incontinence, chronic urinary tract infections, urinary bladder tumors.
Urinary incontinence mostly affects women (approximately 10 million in the U.S.A. alone) primarily after childbirth or due to old age. In men, urinary incontinence often occurs as a complication of surgery or old age (approximately 3 million in the U.S.A).
Incontinence has serious economic, health, social and psychological consequences. Its estimated cost to the health system in the United States in 1993 was US $16 billion. It leads to chronic and severe skin irritation in the genital area, an increase in urinary infections and urosepsis. Fear of incontinence and odors in public cause incontinent people to severely restrict their social activities. The impact on the mental health of the affected people may be even more devastating than the social and health consequences. They suffer severe embarrassment, loss of self-esteem, depression and anxiety.
Urinary incontinence can be divided into four groups:
Stress Incontinencexe2x80x94is the involuntary release of urine due to a sudden increase in the intra-abdominal pressure caused by laughing,, sneezing, coughing, running, etc. This is the most common type of incontinence and in women may be the result of anatomical changes in the pelvic organs after childbirth, estrogen deficiency, unsuccessful surgical repairs for incontinence or pelvic irradiation. In men, it often happens after surgery for benign enlargement of the prostate gland or after radical removal of the prostate.
Total Incontinencexe2x80x94is the continuous leak of urine entering the bladder due 15 to failure of the sphincteric muscles.
Urge Incontinencexe2x80x94is involuntary loss of urine due to involuntary bladder contractions. This type of incontinence mostly affects the elderly who leak until they reach a toilet.
Mixed Incontinencexe2x80x94is a combination of stress and urge incontinence. This condition is more common in elderly women than men.
Ideally, treatment of incontinence should provide permanent dryness and is easy to perform.
Phannacological treatments of bladder dysfunctions are based either on estrogen replacement for treating post-menopausal vaginal and urethral atrophy or on agents affecting the tonus of the bladder muscle. Since affected elderly women suffer from both hormonal deficiency and urinary incontinence, both types of agents are usually prescribed simultaneously.
Surgical treatments are based on restoring the anatomical changes causing the incontinence. Although in the short-term most surgical procedures restore continence, the long-term prognosis is usually unsatisfactory. Moreover, surgery entails morbidity and high expenses.
Conservative/behavioral treatments are based on pelvic floor muscle exercises, bladder training, biofeedback, vaginal cones, low-frequency electrostimulation of pelvic floor muscles, intravaginal bladder neck support pessaries, urethral meatus suction cups and intraurethral devices. Conservative treatments are time consuming and require the patients"" understanding, cooperation and persistence.
Devices which have been used to obtain almost immediate dryness in incontinent people can be divided into two groups:
(1) Urethral Plugs/Inserts
These comprise a flexible rod having, a 14 Ch. (approximately 4.5 mm) diameter and a length adjusted to fit the length of the patient""s urethra. The rod has an inflatable device on its bladder end and a flange at other end. After insertion of the device, the device is inflated in the bladder. The device and the flange, maintain the device in its proper position within the urethra. The device and rod form a mechanical barrier to retain the urine within the bladder. The device must be deflated and the device removed and discarded prior to voiding,. Such inserts are known in the art, for example, the device known as RELIANCE produced by UroMed Corp., U.S.A. Since insets are discarded after each voiding and replaced with a new one by the patient, manual dexterity of the patient is required. Insertion of an insert into a female has the risk of pushing vaginal and perineal bacteria into the bladder and insertion of an insert a few times a day increases this risk The inconvenience of removing and inserting a new device and its costs, in addition to the infection risk, are the major disadvantages of these devices.
(2) Valve Catheters
These comprise a tube with a valve at one end. The bladder end of the device typically has a device or flanges for retaining the device in place and a flange at the other end to prevent migration into the bladder. The valve is opened for voiding through the lumen of the catheter with the help of an external magnet. The tube typically has a 18 Ch. (6 mm.) to 20 Cb. (approximately 7 mm) diameter and a length adjusted to fit the patient""s urethra. For male incontinence, an active intraurethral Foley-type catheter is used. This device has a retaining, device at its bladder end and another smaller device under the prostate for fixing the device in place. The magnet activated valve is situated at the end of the device near the distal end of the urethra. Active inserts are typically left indwelling up to 4 weeks and are then replaced.
Examples of such catheters are disclosed in U.S. Pat. Nos. 5,030,199 and 5,234,409. Valve catheters are more convenient for the patient than the inserts; however, in females they cause ascending infection because they connect the bladder with the vulva which is rich in pathogenic bacteria, especially Escherichia Coli. Even with continuous use of antibiotics, infection is inevitable in the majority of cases. During prolonged use of cathetersor inserts in female patients, a relaxation of the urethra occurs and the patients may start to leak around the device. Unfortunately valve catheters and inserts are unavailable in increasing diameters.
A significant disadvantage of both the inserts and the valve catheters is the discomfort felt by the patient especially when sitting and during sexual intercourse (felt by the patient and the partner).
The present invention therefore provides a device for the treatment of urinary incontinence in which the disadvantages of the prior art devices are substantially reduced or eliminated.
(3) Urinary Bladder PIugs
U.S. Pat. No. 4,850,963 to Sparks et al. discloses a bolus for insertion in to a urinary bladder for the treatment of urinary incontinence. The bolus contains a ferromagnetic material and has a specific gravity greater than that of urine. The bolus is maintained at the urinary bladder outlet to the urethra under the influence of gravity so as to prevent the flow of urine into the urethra. For voiding, the bolus is displaced from the opening using an external magnet.
Nearly half of all women experience urinary tract infection (UTI) at some point in their lifetime and most of these infections are confined to the bladder. Isolated UTIs can be treated by short and effective antibiotic treatment. However, recurrent UTIs often occur in women due to antibiotic resistant bacteria. In this case complicated infections often exhibit multidrug resistance and necessitate longer antimicrobial drug administrations.
Treatment of UTIs often requires urinary levels of antimicrobial drugs that are several hundred times greater than those allowable in the blood. Many antibacterials cannot be used in UTI because, when taken orally or intravenously, they do not attain the required concentration in the urine, without exceeding the allowable limit in the blood. It would therefore be desirable to be able to continuously introduce antimicrobial drugs continuously and directly into the bladder.
Even after resection, bladder tumors may not only recur but may also invade deeper in the bladder wall. Due to the heterogenity of these tumors (from low-grade tumors showing a benign course to highly malignant high-grade tumors), there does not exist a single approach to the surveillance and treatment of these tumors. Intravesical drug therapies are often used for reducing tumor recurrence. In this approach an immunotherapeutic or chemotherapeutic agent is inserted into the bladder through a catheter. This treatment is typically repeated once a week for 6 weeks and then once a month for a period of 6-12 months. However, periodic treatment has not been established as being effective in altering the progression of the tumor. Continuous local treatment with chemotherapeutic or radioactive materials may treat or prevent not only superficial tumors but also deep tumors as well. It would therefore be desirable to be able to introduce antitumoral drugs continuously and directly into the bladder.
During filling, the bladder muscle relaxes for keeping the intravesical pressure low while it contracts for voiding. Certain diseases such as spinal cord injuries, diabetes, multiple sclerosis, or hormonal changes after menopause or old age in both sexes may cause a hypo contractility or, paradoxically, hyper contractility of the muscle. In atonic bladder, pharmacological treatment is not very effective. In hyperreflexic bladder, drugs for relaxing the bladder cause constipation and mouth dryness and are therefore not tolerated well by the patients.
Diagnosis of bladder dysfunction requires continuously monitoring various bladder parameters during filling and/or voiding. These measurements usually are made by inserting a catheter connected to a measuring device into the bladder. This is done for example, in uroflowmetry (measurement of urinary flow rate) which is non-invasive, simple and inexpensive. However, its sensitivity and specificity are low. Cystometry is an invasive technique for measuring bladder capacity, compliance and muscle tonus. Pressure-flow study is an invasive and costly test for distinguishing patients with low urinary flow due to obstruction or bladder antonia, from those with high intravesical pressure and high urinary flow. It is therefore a need in the art for a simple and inexpensive technique for intravesicular monitoring.
In the diagnostic procedure known as xe2x80x9curodynamicsxe2x80x9d, the bladder is filled through a catheter, and the response of the bladder is monitored. Available 24 hour urodynamic monitors have catheters or wires passing trough the urethra, connecting sensors inserted into the bladder to a recorder. The connecting wires and catheters inadvertently introduce pathogenic bacteria from the genital areas into the bladder. It is therefore desirable to be able to monitor bladder function over several cycles of filling and voiding without the need for such wires or catheters.
Diagnosis of some intravesical pathological conditions often involves inserting an endoscope into the bladder and optically scanning the bladder walls. In cases of bleeding in the ureters or the kidneys, the observation of blood coming through the ureteral orifices allows determination of the origin of the bleeding. However, if the bleeding has temporarily stopped at the time of the examiation, or if the blood concentration in the urine is insufficient to make the urine red or pink, endoscopy is of little value in reaching a diagnosis. In such cases more invasive procedures are performed in order to enter the upper urinary tract. It is therefore desirable to be able to monitor the bladder over long periods of time.
Bladder shape during filling and its contraction during voiding is important for the diagnosis of certain bladder pathologies. These functions can be followed in fluoroscopy and by sonography. These techniques however are not accurate and cannot be used for monitoring changes in bladder shape over long periods of tie. It would therefore be desirable to be able to continuously image the bladder interior over long periods of time.
The present invention therefore provides a device for continuous monitoring of the bladder interior and for the treatment of bladder disorders in which the disadvantages of the prior art devices are substantially reduced or eliminated.
The present invention provides a flexibly resilient body having a non-spherical shape, for insertion into an anatomical cavity such as a urinary bladder. The non-spherical shape may be formed, for example, by introducing one or more grooves or protrusions onto the surface of a sphere or by introducing a channel through a sphere. The body may be completely solid, or may contain a fluid in an interior lumen. The body is compressed prior to insertion and then allowed to expand after insertion in the cavity. In the case of a body configured to contain a fluid in a lumen, the body may be inserted into the cavity in a collapsed state with no fluid in the lumen. After insertion the body is expanded by introducing the fluid into the lumen. The body has a magnetizable portion allowing it to be positioned in an outlet of the cavity by means of a hand-held magnet placed in the vicinity of the cavity. The hand-held magnet is also used to rotate the body in the outlet of the cavity.
The body is used for the intermittent sealing of the outlet for preventing inappropriate release of fluid from the cavity. Sealing the outlet involves rotating the body in the outlet into a sealing orientation in which fluid is unable to flow around or through the body. Rotation of the body is done without displacing it from the outlet. Unsealing the outlet to allow voiding of the cavity involves rotating the body into a non-sealing orientation in which fluid flows around or through the body. The body is preferably coated with a hydrophilic coating to reduce frictional forces between the body and the wall of the outlet in order to facilitate rotation of the body in the outlet.
The body may also be used for such purposes as, for example, delivery of drugs, imaging thecavity, and measuring intravesicular parameters such as pressure in the cavity or the composition of a body fluid in the cavity such as urine.
The invention is entirely confined to the cavity As will become apparent in the description below, the body is easily inserted and removed. It may be left in the cavity for prolonged periods of time with minimal risk of encrusting or causing infections and is displaced within the cavity at will using a hand held magnet. The invention is comfortable for the patient and does not interfere with the daily activities of the patient including sitting, jogging, riding, or sexual intercourse.
In its first aspect the invention thus provides a resiliently flexible body having a magnetizable portion for use in medical procedures within an outlet of a cavity of an individual, the body having a non-spherical shape and configured to rotate within the outlet between a sealing orientation and a non-sealing orientation.
In its second aspect the invention thus provides a system for use in medical procedures within a cavity of an individual comprising a body of the specified type and one or more devices from the list comprising:
(a) an applicator for inserting the body into the cavity or for removing the body from the cavity, the applicator fitted at an end thereof with a gripping device for releasably gripping the body; and
(b) a rotating member comprising a magnetizable portion for rotating the body in an outlet of the cavity between the sealing orientation and the non-sealing orientation.
In its third aspect the invention thus provides a method for treating urinary incontinence in an individual comprising the steps of:
(a) compressing a body of the specified type;
(b) inserting the body into a urinary bladder outlet of the individual;
(c) expanding the body in the urinary bladder outlet;
(d) rotating the body within the urinary bladder outlet into a sealing position for sealing the urinary bladder outlet; and
(e) rotating the body within the urinary bladder outlet into an unsealing position for voiding the urinary bladder.
In its fourth aspect the invention thus provides a method for releasing one or more substances into a cavity of an individual comprising the steps of:
(a) loading the one or more substances into a body of the specified type, comprising a compartment containing the one or more substances;
(b) compressing the body;
(c) inserting the body into the cavity; and
(d) expanding the body in the cavity.
In its fifth aspect the invention thus provides a method for monitoring the interior of a cavity of an individual comprising the steps of:
(a) compressing a body of the specified type, comprising one or more devices for monitoring the cavity;
(b) inserting the body into the cavity;
(c) expanding the body in the cavity; and
(d) transmitting signals from at least one of the monitoring devices to a receiver.
In its sixth aspect the invention thus provides a method for imaging the interior of a cavity of an individual comprising the steps of:
(a) compressing a flexibly resilient body of the specified type, comprising a device for imaging the cavity;
(b) inserting the body into the cavity;
(c) expanding the body in the cavity; and
(d) transmitting signals from the imaging device to a receiver.
In its seventh aspect the invention thus provides a method for releasing one or more substances into a cavity of an individual comprising the steps of:
(a) providing a body of the specified type, comprising a pump fed by a reservoir;
(b) loading the reservoir with the one or more substances;
(c) inserting the body into the cavity; and
(d) activating the pump so as to release the one or more substances into the cavity.